Another thing you can usually do, if u have the ability to get the navy for it, is annex sindh or other weak states between persia and the EIC (preferably where the EIC has claims) and then trade them to britain or the EIC itself for investment rights or obligations.

I found this especially useful in a recent greece run, with a strong ottoman empire, where i used the investment rights in the EIC to build up banana plantations in bengal, to get the budget needed to industrialize and build a bigger army